French prisoner Nicolas Cocaign killed his prison cellmate and then consumed his lung. Image Credit: AFP

Rouen: A French prisoner killed his cellmate and devoured his lung after authorities ignored appeals for psychological assistance, he told a court as his trial opened Monday.

Nicolas Cocaign, 39, told judges in the northern city of Rouen that he had had a long history of mental problems even before he sliced open his victim, ripped out his lung and fried it on a makeshift stove in their cell.

"No one was listening to me," the bearded and tattooed detainee told the court. "I made several appeals for help, saying I was a man capable of being dangerous. I took action, and then they took me seriously."

Cocaign is charged with killing cellmate Thierry Baudry in January 2007 by punching and kicking him, stabbing him with a pair of scissors and suffocating him with a rubbish bag.

Prosecutors say he sliced open Baudry's chest with a razor blade, removed a rib and pulled out an organ which he at first believed to the man's heart, but which in fact was a lung.

He is said to have eaten part of the lung raw and then fried the rest of it with some onions.

Under interrogation before the trial, Cocaign said he had turned cannibal because he wanted to take the victim's soul, but in court Monday he stressed his troubled background and mental instability.

Born in 1971, he was abandoned by his 21-year-old homeless mother and cared for by the state until he was adopted aged three. From the age of six he was already under the care of a psychologist.

Reports from his childhood suggest he had difficulty telling right from wrong and his mental difficulties worsened when he was allegedly raped, aged 13. After this he developed "violent sexual compulsions".

He was convicted of drug possession at age 22 and was later hospitalised on several occasions with mental illness. He complained to the court that he was not given drug treatment after release, despite asking for it.

"My compulsions were still there, so ..." he said.

Mental health experts are to testify during the course of the trial this week as to whether Cocaign was sufficiently sane to face criminal charge for his acts. A verdict is expected on Thursday.

Should governments have to pay compensation to inmates for having to serving time in poor living conditions? Should convicts requests to seek psychiatric help be granted?